My Ramanujan Number = 6

Balasubramanian Raman	coauthored with	Ananda S Chowdhury
Ananda S Chowdhury	coauthored with	Robert W. Robinson
Robert W. Robinson	coauthored with	Paul Erdős1
Paul Erdős1	coauthored with	Hans Arnold Heilbronn
Hans Arnold Heilbronn	coauthored with	Godfrey Harold Hardy
Godfrey Harold Hardy	coauthored with	Srinivasa Aiyangar Ramanujan